Control and monitoring device



March 1954 .c. R. CURNUTT CONTROL AND MONITORING DEVICE Filed Aug. 6, 1951 INVENTOR: g/QFVQ/ Q. Cu/fluff 'ATTORNEY Patented Mar. 9, 1954 CONTROL AND MONITORING DEVICE Clarvel R. Curnutt, Fort Worth, Tex., assignor to 7 Consolidated Vultee Aircraft Corporation, San Diego, Calif., a corporation of Delaware:

Application August 6, 1951, Serial No. 240,573

, 4 Claims. 1

This invention relates to electric circuit controlling devices and more particularly to control devices of novel construction for use in electrical circuits for controlling and indicating alternating current flow therethrough.

An object of the present invention is to provide an improved electrical warning means for simultaneously controlling and monitoring the flow of current through a circuit to a load device.

Another object of the invention is to provide an improved form of indicating mean for determining the electrical condition of a remotely located load device.

Another object of the invention is the provision of a novel current-flow control and indicatin device particularly adapted for use on an instrument panel wherein it produces a visual signal to indicate to the operator the condition of an electric circuit.

Another object of the invention resides in providing an electric circuit condition indicator of improved and novel construction embody n transformer means for operating signalling lights.

A further object of the invention lies in the provision of a novel visual signalling device for use in electrical circuits utilizing electric currents of small values, which currents are normally too weak to operate an indicating bulb.

A further object of the invention is to provide a novel current-flow control and signallin means which controls and affords a. visual indication of the operating condition of devices of both intermittent and constant load types.

A still further object of this invention is the provision of animproved and simplified currentfiow control and signalling device for use with remotely located loads which does not necessitate the use of relays, complicated wiring, or extraneous sources of current supply.

A still further object of the invention is to provide a current-flow control and circuit condition indicator which is of simplified and compact construction, neat in appearance, and inexpensive to manufacture.

Other objects and features of this invention will be readily apparent to those skilled in the art from the following specification and appended drawing illustrating certain preferred embodiments of this invention in which:

Figure 1 is a front elevation of an electric circuit controlling and monitorin device in accordance with the present invention.

' Figure 2 is a side elevational view'of the device of Figure 1, with its cover open, and with the de- 2 vice mounted in operative position on an instrument panel.

Figure 3 is a circuit diagram showing the de- Having reference now, in greater detail, to the drawing, wherein like parts are designated by lik numerals throughout the specification and drawing, the electric circuit controlling and monitoring device of the present invention is desi nated generally therein by the numeral [0. Figure 2 illustrates device H] as installed in operative position on an instrument panel I l, arranged to be viewable on the front face thereof and to be readily accessible to an operator. Since the present invention has particular application when used in aircraft, it will be assumed that instrument panel II is located in the pilot compartment of an aircraft, but without implica-' tion that the invention cannot be employed'in other locations of similar environment andhaving similar problems.

Control device l0 comprises a generally rectangular housing or box l2, openable atone end, with a closing cover I3 hingedly mounted as at M on one edge of the housing l2. Supported within housing I2 is a usual three-position control switch IS with an actuating lever Hi. The switch I5 is fixedly mounted upon the front wall I! of housing [2 by a pair of lock-nuts l8 and I9 cooperatin with a cylindrical, exteriorly threaded, mounting portion 2| provided by the switch 15.

A pair of signal lamps or indicator lights 22 and 23 are located on housing wall l1, being fixedly secured thereto, on either side of actuatin lever l6, by mounting nuts 24. The signal lamps 22 and 23 are preferably of the glow type, for a reason to be hereinafter discussed. Signal lamps 22 and 23 embody faceted, jewel-type, lens 25, which may be colored for the convenience of and more ready observation by the operator.

Also disposed within housing [2 are a pair'of step-up transformers 26 and 21, each comprising a generally E-shape magnetic core 28 and coil windings 29 fitted about the central leg3l of core 28. A plurality of nut and boltassemblies 32 secure the transformers 26 and'2l to the base 33 of housing 12. 1

Three terminals 34, 35, and 36 are mounted upon end wall 31 of housing 12, these terminals comprising, respectively, binding posts 38, 39 and 40, headed at their ends and threaded at their outer ends. Suitable insulating washers 4| are provided on each of the posts at either side of wall 31 to insulate their posts from housing I2. Binding nutss42an lv 43 are fitted upon the threadedouter ends of'each post for the connection of conductors thereto. Terminals 34 and 36 are adapted to accommodate the lead Wires of a load device to be serviced, while terminal 35- serves as a current supply terminal, as will be hereinafter further discussed;

A terminal strip 44 is located withinhousing l2,

spaced from the front wall I! to lie between the pair of transformers 26 and 21 and'the elements carried by the front wall l1. Terminal strip 44 embodies mounting flanges 45 which cooperatewith a pair of the transformer nut and bolt assemblies 32 to fixedly mount terminal strip .44 upon housing base 33.

A pair of mounting brackets 46 vareprovided upon the'exterior of housing I2,.on opposite walls thereof. Nut and bolt assemblies 41 secure the brackets 46-to instrument panel ll tomount the control device ID in the required positionthereon opposite an opening in the panel so that the 43 of transformer 26 are connected, as by solder-- ing, to acommon terminal 53 provided on the terminal strip 44 byconductors 54 and 55, while the'other indicator light 23 and one end of the secondary coil 52 of the second transformer 21' are-similarly'connected to a second common ter minal 56 by conductors51- and-58.- Leads-6i and 62 connect, respectively, the'indicator light-22 and the-other end of secondary coil49 of trans-- fo'rmer26 to a common grounded-terminal: 63"

carried by terminal strip 44. A 'second'pairof leads 64' and 65 connect," respectively, the indicator--light 23 and the opposite end of secondary coil 52 of transformer 21 to a second common grounded terminal '66 afiorded by terminal strip One end of primary coil 48 of transformer 26- is connected bya conductor 61 to the control switch l while its opposite end is connected bya lead68" to bindingpost 34. The primary coil 5 I of transformer 2! is similarly connected, with a-lead'llconnecting one end of primary coil 5| to switch l5-and with a second lead-l2 connecting the oppositev end thereof to binding post 36. A-lead 13- extends from control switch [5 to current supply terminal 35, and a second lead 14 connects this terminal 35 to a suitable source of power,suc'h as alternating current generator 15; illustrated in Figure 3.

Figure 3 illustrates a circuit wherein the con-' trol device I0 is shown employed for thecontrol:

and intermittent operation of a reversible-motor,

which is-indicated generally by the numeral 16-;

It is understood that reversible motor 161s merely illustrative of a load device that maybe used with the present indicator switch hand thatno limitation is to be implied in citing the reversi:

ble motor as an example.

As shown in the drawing, the reversible motor 16 includes in its circuit a pair of usual limit switches 17 and 1B which serve to determine the amount of rotation of the motor in opposite directions. Suitable mechanical connections, indicated generally at 19, are provided between motor T6 and its associated limit switches T1 and 18 so that when the motor 'lfihas rotated in one direction a sufiicient amount to perform a-desired operation a limit switch will be actuated through the mechanical interconnection therewith to break themotorcircuit and stop the motor. On rotation of the motor in the opposite direction the extent of movement is determined by the opposite limitswitch,:which functions in like manner'asthefirsttobreak the motor circuit and thereby bring the'motor to rest. The particular type or the particular mechanism employed to effect the desired operation of the limit switches forms no part of the present invention and therefore no detailed description thereof. is necessary.

As shown iriJiigure 3, indicator switch iscoupled tomotor l'fie'bylead wires 8| and 82-'which,ree

spectively, connectloadterminals:34sand'35 to the circuit of limit switches--11 and '18 wherebyicur rentmaybe suppliedto the-motor 16 from power source!5.through:indicator switch l0.

Withindicator switch lll connectedto motor'16 I5 is actuated to complete thecircuit from the power source 15.

Assuming lever I6 is moved from its neutral position to closethe circuit through the, primary coil 48 'of. transformer 26"current will then be fed through seriallyconnected limit switch. '17 "to the motor 16 to permit rotation thereof'until it has performed adesired operation and liinit swit'c'hTl is operated to break the. circuit. With current flowing through primary coil 48' a current will be indu'cedimsecondarycoil 49 sufiicient to operate glow lamp 22; Lamp 22 will continue to provide avisual-Sig'nal tc-the operator that current 'is flowing-to motor 16 untilthemotor 16 completes -'a required operation *at' which time limit switch 11' breaks the circuit of primary coil 48. When-lamp 22 ceases toglo'w the operatoris thereby informed: that the motor: 16 has completed-itsoperation Now if it-is desired to re-- verse the motor-1 6 to returnit; and'such apparatus as-may be controlled 'byit;to-their original conditionzlever l 6 willbe movedto close the circult of primary coil 5l of transformer 21 thereby to feed current front power source- 15" toinduce voltage in secondary 52r= to ignite-lamp 23' andto passcurrent through serially connected limit switch-I8 'to motor-l6:, causing the latter to rotate in the reverseddirection-until limit switch 'ld isoperated to cut ofi current-fiow to "motor 16. The

completion of this latter operationdsmade known. to tlie operator but inlthis instance, by reason-ofthe lamp 23-ceasing-.to-glow.-

In practice, as is well understood to-thoseskilled inithe art', the current-provided 'inaircraft-' for l effecting the: operation of various of: its' accessory actuating motorsitm effecti operation uof i various accessories, control imembers; constant load members, such :heaters; i etcris necessarily small; This usual current is of such asmall magnitude -that. without employing de'- vices such asetransformersifi and:21:,*as:-in:the present: i invention; signalliilgu. lamps I will not operate. In the present "invention? transformeers 26 and 21 are employed to produce a secondary voltage sufficient to operate glow type of indicating bulbs. The ratio of turns between the primary and secondary turns of the transformers 26 and 21 is such that for very small primary currents sufiicient secondary voltage is obtained that a glow can operate. It is merely a matter of experience to determine the proper size of transformer.

A glow type of bulb, that is, a bulb comprising an enclosing vessel having therein an ioniza ble atmosphere, is preferred for use in the present invention, since it is dependent for operation on voltage strength rather than current strength, and the required voltage strength is readily obtainable with the use of a step-up transformer. Further, if secondary voltage should be increased to a relatively high value, on increase of the primary current, occasioned by the occurrence of a short-circuit or other current increasing conditions in the line, a glow type tube will not burn out as would a constant voltage incandescent type of bulb.

From the above description, it is readily apparent that control device I of the present invention affords a simple, inexpensive, and highly reliable means for controlling and simultaneously monitoring the operation of intermittent load devices. These dual functions are here accomplished without requirement of complicated wiring, or extraneous electrical devices, in association with the controlled load or without requiring any special adaptations of the device being controlled.

The invention has been above described in conjunction with an intermittent load device, however, it is here specifically noted that control and monitoring device I0 is as readily adapted for use with constant load type devices such as heaters or motors required to run continuously. Figure 4 illustrates a circuit wherein a heater 85 of conventional design, is to be serviced by control device I0. As shown, the heater 85 is connected by a lead 86 to load terminal 34 and therethrough to the primary coil 40 of transformer 26 (though it could as readily be connected to load terminal 36 and to the primary coil 5| of transformer 21). With lever I6 moved to close the circuit from the power supply I5 current will flow through primary coil 40, inducing a voltage in secondary coil 49 to operate lamp 22, and placing heater 85 into operation. Lamp 22 will continue to glow so long as power continues to be supplied to heater 85. If lamp 22 fails to glow or should go out, the operator will be informed that a defect exists in the heater circuit. A motor adapted to be run constantly could be substituted for heater 85, being connected in similar manner to either the primary coil 48 of transformer 26- or the primary coil 5I of transformer 21 since but one circuit need be maintained to the load device, and failure of lamp 22 to operate or a cessation of glow will provide an indication to the operator that trouble exists in the motor circuit.

Figure 5 illustrates, diagrammatically, a modification of the invention wherein but one transformer is utilized and which is indicated at 9|. The modification, as a unit, is identified by the numeral I 0a. In this modification a conventional double-pole, double-throw type of switch, indicated generally by numeral 92, is substituted for switch I5 of the preferred embodiment. Glow lamp 22 is connected by appropriate conductors to a contact 93 of switch 92 and to ground. Transformer 9I includes a'primarycoil 94, a core 95,and a secondary coil 96, with primary coil 94 being connected to a terminal 91 of'switch 92 and to the current supply treminal 35, and with secondary coil 96 being connected to a terminal 98 of switch 92 and to ground. Glow lamp 23 is connected to a contact 99 of switch 92 and to ground. Leads IOI and I02 connect contacts I03 and I04 of switch 92, respectively, to load terminals 34 and 36. An actuating lever I05 is provided for closing the circuit to either the load terminal 34 or the load terminal 36.

The modification of Figure 5 is shown in use with a'constant load device, which, for example, is a reversible motor required to run constantly in either clockwise or counter-clockwise direction, and responding to changes in polarity of current fed thereto. This motor is indicated in the drawings generally by the numeral I06, and is shown connected to load terminals 34 and 36 of control device No by conductors I01 and I08. To start the motor I06 lever I05 is manually operated to place the contacts 93 and I03 in circuit. This operation permits current to flow 'from power supply 15 through primary coil 94 to contact I03 and therefrom to load terminal 34 and thence to motor I06 to actuate the latter. The current flowing through primary coil 94 induces a voltage in the secondary coil 96 which, because of the proper selection of primary and secondary winding turns, will be sufficient to operate glow lamp 22. So long as lamp 22 continues to glow a. visual indication is provided the operator of the rotation of the motor I06. To stop the motor I06 the lever I05 is moved to its neutral position to stop the flow of current to the motor. If it is then desired to rotate the motor in the opposite direction lever I05 is moved to throw contacts 99 and I04 into circuit to connect the lamp 23 into circuit .withthe secondary coil 96 and to pass current through load terminal 36 to motor I06. Again motor I06- continues to operate and lamp 23 to glow until the lever I05 is returned to neutral or a. defect occurs in the motor circuit.

From the above description afforded of the preferred and the modified embodiments of the invention, it is thought that the construction and operation of the invention will be fully understood, and no further explanation is required.

While certain preferred embodiments of the invention have been specifically disclosed it is understood that the invention is not limited thereto as many variations will be readily apparent to those skilled in the art and the invention is to be given its broadest possible interpretation within the terms of the following claims.

WhatIclaim is:

1. In a warning system for a remotely located current actuated load having an electrical circuit and a source of alternating electrical current, control means including an electric switch means for effecting a connection between said electrical circuit and said source of alternating electrical current, a pair of visual signal means electrically connected to said switch means and each having a connection to ground, and a single transformer, said transformer having a primary coil serially connected to said switch means and said source of alternating electrical current and a secondary coil interconnected between ground and said switch means, said primary coil inducing a voltage in said secondary coil to opaccuses erate awisual signal means on'cperation ofi said: switchimeans to permit-current fiowto said elec:--:v trical circuit, said visual: signal means-1 servingzto monitor the -flow' "of current" to" said; electrical".

circuit;

2ziIn'a warning system for .a remotely locatecli current'actuated loadhaving: an electrical cir,-- cult and a source of alternating electrical cure rent, control means including double-pole, double-throw switch for effecting; a: 'connection: between said electrical circuit andsaid sourceof alternatingelectrical current, a pair ofrvisual.

signal means and a single transformer, a pair: of. conductors connecting said SWitCh tOr said electrical circuit, conductors connecting-said pair: of visualsignal means 'to said switch .andrto. ground, 1 said transformer having aprimary. coil and 'aysecondary coil, conductor means connecting said primary coil to said switch and to said;v source of alternatingelectrical current, and-con ductor means connecting said secondarycoil between' ground and said switch, saidprimaryzcoil-- inducing a voltage in' saidisecondary coil to opeerate a visual signal means on operation or saidswit'ch'means to an ON position topass: current: to saidelectrical circuit, said visual signal means serving to monitor the flow of currenttto-said electrical circuit.

3. In a warning'system for a reversible'motorhaving; an electrical circuit and a source'of-alternatingl electrical current, control means including a double-pole; double-throwswitch for efiecting a' connection. between said electrical circuit and said source of alternating electrical current to control the direction of rotation of said; reversible motor, apair of glow'lampsand. a single transformer, a pair ofconductors con-, necting. said 'switch' to: said electrical circuit,

conductors connecting said pair oi -glow lamps tolsaid switch and to ground, said transformer having a primary coil and a'secondary coil, con.- ductor means connecting said primary coil to said switch and to said source of alternating e1ectrical current, and conductor means connecting: said; secondary coil between" ground and said: switch, said primary coil, inducing a voltage in said secondary coil to operate a glow lamp on operation of said switch means to, an ON position to pass' current to said, electrical circuit to effect rotationsofi said reversible motor, said glowlampz servingto; monitor the flow of currentrto:

said electrical circuit.

4; A: circuit controlling and monitoring device forva current, actuated load means having, an

electrical circuit, comprising a double pole, douebleethrow switch' for eflecting a connection& betweenisaidelectrical-circuit and a source of cur.

.rent, a pair of visual signal means electrically connected tosaid switch; a transformer having; a-uprimarycoilanda secondary coil, conductor means connecting:- said primary coil to= said switch and said sourceof current, and conductormeans-connecting said secondary coil between ground and saidswltch, said switch including; an: actuating lever for selectively connecting, said visual signalmeans incircuit with saidsecondary;coil, said primary coil inducing a voltage in said secondary coil to operate'a visual signal means on operation of-saidswitch to anON positionto-pass current to said electrical circuit. CLARVEL R.- CURNUTT.

References Cited in the file of this patent UNITED STATES PATENTS 

